Zeta potential distribution of 1 nm particles
Below 5 nm, due to lack of signal, with most analytical systems it is difficult to measure electrokinetic potentials (EKP). Either the particles and macromolecules (NP´s) are too small or the concentration is too low. With the particle charge analyzer Stabino® and the zeta potential analyzer ZetaView® the analysis is possible in many cases.
Particle Charge Characterization with Stabino®
The measurement principle of the particle charge analyzer Stabino® is based on the streaming potential which itself is proportional to the better known zeta potential. Many restrictions encountered with zeta potential analysis are not present with streaming potential, which is an electrical measurant, instant and has no shortcomings.
After describing the principle in detail, a few typical examples are given to demonstrate the wide size range in which this principle is applicable and how easy it is to extract a variety of information about the ionic particle interface charact
- isoelectric point of 1 nm proteins
- functional charge density of 20 µm CNTs
- stability of coatings by trend analysis
Electrophoresis zeta potential, Brownian particle size & electroosmosis: direct observation in the laser ZetaView® scattering video microscope by Nanoparticle Tracking
Total particle charge characterization shows functionalization of carbon nano tubes
Frequently, functionalization of particle interfaces, in particular with ionic end groups, is done to make dispersions stable or to prepare them for specific reactions. Charge titrations with calibrated ionic polymers deliver charge in meq per gram or surface area, depending on the given parameter. With the particle charge analyzer Stabino® the result is obtained in a few minutes.
Efficient particle charge mapping with Stabino®
Titrating ionic liquids to a dispersion delivers comprehensive insight in the ionic behavior of a sample with respect to stability, functionality, coagulation and dispersability. As a charge monitor, the streaming potential of the Stabino® is a very effective candidate for particle interface potential (PIP). It is applicable to macromolecules as well as to particles. In addition, the mixing of the titrands into the sample and the measurement of the PIP itself is achieved within a few seconds. This makes the particle charge analyzer Stabino® a Charge Mapping Master. Besides the concentration of the reaction partners, no physical parameter entry is necessary. The principle is explained and accompanied with a variety of examples.